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INFO: rcu detected stall in batadv_nc_worker

Status: upstream: reported on 2023/06/13 20:27
Reported-by: syzbot+42b636738d776704a740@syzkaller.appspotmail.com
First crash: 323d, last: 12d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: rcu detected stall in batadv_nc_worker origin:lts-only C done 14 23d 301d 0/3 upstream: reported C repro on 2023/07/06 06:16
upstream INFO: rcu detected stall in batadv_nc_worker cgroups mm 7 1610d 1612d 0/26 closed as invalid on 2019/12/04 14:04
upstream INFO: rcu detected stall in batadv_nc_worker (2) kernel 4 1575d 1575d 0/26 closed as invalid on 2020/01/09 08:13
upstream INFO: rcu detected stall in batadv_nc_worker (3) batman C done inconclusive 208 3d13h 1308d 0/26 upstream: reported C repro on 2020/10/01 10:35

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (1 GPs behind) idle=c01/1/0x4000000000000000 softirq=16773/16774 fqs=4 
	(detected by 0, t=10502 jiffies, g=21973, q=126)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1204 Comm: kworker/u4:4 Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0xc/0x12
Code: 56 57 41 50 41 51 41 52 41 53 e8 bf 0a 00 00 41 5b 41 5a 41 59 41 58 5f 5e 5a 59 c3 66 90 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <3c> 01 75 02 5a c3 56 0f b6 f0 e8 c5 ff ff ff 5e 5a c3 66 90 55 48
RSP: 0018:ffffc90000dd0c30 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 1ffffffff22ba3a5 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff915d1d20
RBP: dffffc0000000000 R08: dffffc0000000000 R09: fffffbfff22ba3a5
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff22ba3a6
R13: ffffffff915d1d30 R14: ffffffff915d1d28 R15: ffffffff915d1d20
FS:  0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f082691f800 CR3: 000000007824e000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:590 [inline]
 queued_spin_unlock arch/x86/include/asm/qspinlock.h:56 [inline]
 do_raw_spin_unlock+0x137/0x8b0 kernel/locking/spinlock_debug.c:141
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:159 [inline]
 _raw_spin_unlock_irqrestore+0x7d/0x130 kernel/locking/spinlock.c:194
 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline]
 debug_deactivate+0x1b/0x1e0 kernel/time/hrtimer.c:481
 __run_hrtimer kernel/time/hrtimer.c:1654 [inline]
 __hrtimer_run_queues+0x31d/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627
Code: 2b 00 74 08 4c 89 f7 e8 ac 73 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc90004effa20 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920009dff50 RCX: 1ffff920009dfef0
RDX: dffffc0000000000 RSI: ffffffff8a8b3c20 RDI: ffffffff8ad8f380
RBP: ffffc90004effb70 R08: dffffc0000000000 R09: fffffbfff1f7ec19
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920009dff4c
R13: dffffc0000000000 R14: ffffc90004effa80 R15: 0000000000000246
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312
 rcu_read_lock include/linux/rcupdate.h:739 [inline]
 batadv_nc_process_nc_paths+0xb8/0x350 net/batman-adv/network-coding.c:691
 batadv_nc_worker+0x3d4/0x5b0 net/batman-adv/network-coding.c:732
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
rcu: rcu_preempt kthread starved for 10494 jiffies! g21973 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27000 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 3617 Comm: kworker/u4:5 Not tainted 5.15.156-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: netns cleanup_net
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1686 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline]
 __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102
 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:csd_lock_wait kernel/smp.c:440 [inline]
RIP: 0010:smp_call_function_single+0x292/0x530 kernel/smp.c:758
Code: 0f 85 24 02 00 00 44 8b 6c 24 48 44 89 ee 83 e6 01 31 ff e8 90 e4 0b 00 41 83 e5 01 75 0a e8 25 e1 0b 00 e9 eb 00 00 00 f3 90 <42> 0f b6 04 23 84 c0 75 15 f7 44 24 48 01 00 00 00 0f 84 cd 00 00
RSP: 0018:ffffc900040377a0 EFLAGS: 00000293
RAX: ffffffff81747bde RBX: 1ffff92000806efd RCX: ffff8880236a9dc0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004037890 R08: ffffffff81747bb0 R09: ffffed1017367681
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc900040377e8 R15: 0000000000000000
 rcu_barrier+0x262/0x4e0 kernel/rcu/tree.c:4078
 netdev_run_todo+0x381/0xc40 net/core/dev.c:10621
 ip6gre_exit_batch_net+0x41a/0x460 net/ipv6/ip6_gre.c:1651
 ops_exit_list net/core/net_namespace.c:174 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:596
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300
 </TASK>

Crashes (18):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/04/19 08:26 linux-5.15.y c52b9710c83d af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/04/18 09:55 linux-5.15.y c52b9710c83d af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/04/16 03:23 linux-5.15.y fa3df276cd36 0d592ce4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/03/16 21:08 linux-5.15.y b95c01af2113 d615901c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/02/19 18:55 linux-5.15.y 6139f2a02fe0 3af7dd65 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/02/13 20:01 linux-5.15.y 6139f2a02fe0 e66542d7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2024/01/12 21:51 linux-5.15.y 26c690eff0a5 551587c1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/12/08 13:02 linux-5.15.y 8a1d809b0545 28b24332 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/12/03 13:56 linux-5.15.y 9b91d36ba301 f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/11/23 05:07 linux-5.15.y 2a910f4af54d fc59b78e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/11/03 01:50 linux-5.15.y 12952a23a5da c4ac074c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/11/01 06:46 linux-5.15.y 12952a23a5da 69904c9f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/10/05 23:49 linux-5.15.y b911329317b4 db17ad9f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/09/08 18:14 linux-5.15.y aff03380bda4 6654cf89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/09/06 22:17 linux-5.15.y aff03380bda4 72324844 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/11/25 13:30 linux-5.15.y 2a910f4af54d 5b429f39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: rcu detected stall in batadv_nc_worker
2023/07/23 12:10 linux-5.15.y d54cfc420586 27cbe77f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
2023/06/13 20:26 linux-5.15.y 7349e40704a0 d2ee9228 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in batadv_nc_worker
* Struck through repros no longer work on HEAD.